Because this is parabolic motion, the object will reach the height of 68 feet when it's going up AND when it's coming down. In order to find out those times, you set the h on the left side of the equation equal to 68, because h stands for height.
Set that equal to 0 and factor to solve for t:
Using the quadratic formula, we get t = 1.5 and t = 2.5
